The Hazardous Substances Basic Research Program at the University of Cincinnati is a consortium of faculty of the Colleges of Medicine, Engineering, and Arts and Science with the primary goal of developing new methods that will be useful in the microbial degradation of toxic organic substances found in hazardous waste sites and industrial effluents. There are three areas of basic research interests in this proposal, a Biomedical component consists of three projects to investigate the biodegradation and toxicology of three classes of chemical wastes. In Project 1 molecular genetics will be used in the gene engineering of microbes capable of metabolizing environmentally recalcitrant polychlorinated aromatic hydrocarbons. Project 2 will involve the development of microbial systems to aerobically degrade azo dyes and related dye stuffs to innocuous products. Later phases of this project will involve genetic manipulation and modification of microbes to optimize detoxification. Project 3 deals with the microbial degradation of recalcitrant carcinogenic 4 and 5 ring polycyclic and N-heterocyclic aromatic hydrocarbons. Studies in this project will involve the chemical characterization and determination of toxic properties of the degradation products. The Engineering component, Project 4, is directed toward the design and evaluation of novel bioreactors for effective microbial degradation. This project involves evaluation of aerobic and anaerobic methods, i.e. hollow-fiber units, spiral-wound membrane modules and biofilms for biodegradation of hazardous compounds. A major aspect of this project will investigate the ecologic interrelationships in existing and genetically enhanced microbes in communities during the biodegradation of pollutants. The Instrumentation component, Project 5, will involve the further development of Inductively-Coupled Plasma-Mass Spectrometry for the detection of toxicants at the ultra-trace levels. This project will focus on development of methods of detection at the femtogram to picogram levels of chlorine and sulfur containing compounds of interest to the Biomedical and Engineering components. Other compounds of interest in hazardous waste sites will also be studied, particularly metals.